Haworthia plant named ‘AMIHAW1801’

ABSTRACT

A new and distinct  Haworthia  plant named ‘AMIHAW1801’, which is characterized by a fast rate of growth, succulent foliage that is held upright in a spirally-arranged rosette, large, broadly deltoid foliage with coarsely dentate margins, and dark green foliage which is tolerant of high light levels. The new variety has shown to be uniform and stable in the resulting generations from asexual propagation.

Latin name of the genus and species: The Latin name of the genus and species of the novel variety disclosed herein is Haworthia pentagona.

Variety denomination: The inventive variety of Haworthia plant disclosed herein has been given the variety denomination ‘AMIHAW1801’.

BACKGROUND OF THE INVENTION

Parentage: ‘AMIHAW1801’ originated as a naturally occurring, whole-plant mutation of an unnamed Haworthia pentagona plant (not patented). In September of 2013 the inventor discovered the mutation at a commercial greenhouse in Heerhugowaard, the Netherlands, growing amongst a crop of the species Haworthia pentagona. The mutation was noted for its improved vigor and dark green, broad deltoid foliage and was subsequently isolated for further evaluation in order to confirm the distinctness and stability of the characteristics first observed. Upon confirmation of distinctness and stability, ‘AMIHAW1801’ was selected for commercialization.

Asexual Reproduction: Asexual reproduction of the new cultivar ‘AMIHAW1801’, by way of rooting leaf cuttings, was first initiated in March of 2014 at the inventor's commercial greenhouse in Heerhugowaard, the Netherlands. Through eight subsequent generations, the unique features of this cultivar have proven to be stable and true to type.

SUMMARY OF THE INVENTION

The cultivar ‘AMIHAW1801’ has not been observed under all possible environmental conditions. The phenotype may vary somewhat with variations in environment such as temperature, day length, and light intensity, without, however, any variance in genotype. The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘AMIHAW1801’. These characteristics in combination distinguish ‘AMIHAW1801’ as a new and distinct Haworthia cultivar:

-   -   1. ‘AMIHAW1801’ exhibits spirally-arranged succulent foliage,         held upright, in a basal rosette; and     -   2. ‘AMIHAW1801’ exhibits a fast rate of growth; and     -   3. ‘AMIHAW1801’ exhibits large, broadly deltoid foliage with         prominent teeth that are moderately abundant along the proximal         half of the leaf margin and become less prominent and nearly         absent towards the distal portion and apex; and     -   4. ‘AMIHAW1801’ exhibits dark green foliage which is tolerant of         high light levels.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates, as nearly true as it is reasonably possible to make the same in color photographs of this type, an exemplary plant of ‘AMIHAW1801’ grown in a commercial greenhouse in Heerhugowaard, the Netherlands. This plant is approximately 7.5 months old, shown planted in a 10.5 cm container.

FIG. 2 illustrates, as nearly true as it is reasonably possible to make the same in color photographs of this type, the typical foliage arrangement of ‘AMIHAW1801’.

FIG. 3 illustrates, as nearly true as it is reasonably possible to make the same in color photographs of this type, the adaxial surface of the mature foliage ‘AMIHAW1801’.

FIG. 4 illustrates, as nearly true as it is reasonably possible to make the same in color photographs of this type, the abaxial surface of the mature foliage ‘AMIHAW1801’.

BOTANICAL DESCRIPTION OF THE PLANT

The following observations and measurements made in January of 2017 describe averages from a sample set of six specimens of 7.5 months old ‘AMIHAW1801’ plants grown in 12 cm nursery containers at commercial greenhouse in Heerhugowaard, the Netherlands. Plants were produced using conventional greenhouse production protocols for Haworthia plants which consisted of minimal subsurface irrigation and minimal fertilizer applications, and chemical pest and disease control measures against mealy bug, Botrytis sp. and Fusarium sp. as required. Plants were grown under approximately 50 percent shade and no photoperiodic treatments or artificial light was given to the plants.

Those skilled in the art will appreciate that certain characteristics will vary with older or, conversely, with younger plants. ‘AMIHAW1801’ has not been observed under all possible environmental conditions. Where dimensions, sizes, colors and other characteristics are given, it is to be understood that such characteristics are approximations or averages set forth as accurately as practicable. The phenotype of the variety may differ from the descriptions set forth herein with variations in environmental, climatic and cultural conditions. Color notations are based on The Royal Horticultural Society Colour Chart, The Royal Horticultural Society, London, 2015 (sixth edition).

A botanical description of ‘AMIHAW1801’ and a comparison with the parent and closest known comparator is provided below.

-   Plant description:     -   -   Growth habit.—Succulent perennial with foliage growing in a             non-branched basal rosette.         -   Plant shape.—Flattened globular.         -   Height from soil level to top of foliar plane.—12.8 cm.         -   Plant spread.—Average of 18.1 cm.         -   Growth rate.—Moderate.         -   Plant vigor.—Moderate.         -   Propagation.—Type — Leaf cuttings. Time to initiate rooting             — Approximately 20 days at 18 degrees Celsius. Crop time —             Approximately 30 weeks to produce a marketable plant in a 12             cm container.         -   Disease and pest resistance or susceptibility.—Neither             resistance nor susceptibility to typical Haworthia pests and             diseases has been observed.         -   Environmental tolerances.—Adapt to, at least, USDA Zones 10             to 12 and temperatures as high as 40 degrees Celsius; low             tolerance to rain; high tolerance to wind. -   Root system:     -   -   General.—Fine, well-branched fibrous roots. -   Stems:     -   -   Branching habit.—Leaves in a non-branching basal rosettes;             no main branches or lateral branches present. -   Foliage:     -   -   Arrangement.—Spirally arranged in a rosette.         -   Division.—Simple.         -   Attachment.—Sessile.         -   Quantity.—21 leaves per rosette.         -   Shape.—Broad deltoid.         -   Dimensions.—10.4 cm long, 4.4 cm wide, and 1.0 cm thick, on             average.         -   Aspect.—Very slightly concaved and slightly curved downward             at the distal portion of the leaf.         -   Attitude.—Upward to outward.         -   Apex.—Apiculate, with a soft mucronate tip.         -   Base.—Broad cuneate.         -   Margin.—Coarsely dentate with teeth that are moderately             abundant along the proximal half of the leaf margin and             become less prominent and nearly absent towards the distal             portion and apex; teeth have an average length of 0.1 cm and             are colored greyed-green, nearest to RHS 193A. Margins are             not undulated or lobed.         -   Texture, adaxial surface.—Glabrous and smooth with the             exception of the midrib which appears as a shallow             longitudinal groove running the length of the leaf.         -   Texture, abaxial surface.—Glabrous and smooth with the             exception of the midrib which appears as a shallow             longitudinal groove running the length of the leaf.         -   Luster, adaxial surface.—Slightly glossy.         -   Luster, abaxial surface.—Slightly glossy.         -   Color.—Juvenile foliage, adaxial surface — Green to             yellow-green, nearest to in between RHS NN137A and 147A;             fading to a lighter shade of yellow-green towards the base,             nearest to RHS 144A. Juvenile foliage, abaxial surface —             Green, nearest to RHS NN137A, and fading to yellow-green             towards the base, nearest to RHS 144B. Mature foliage,             adaxial surface — Green, nearest to in between RHS NN137A             and 139A, and fading to a lighter shade of green towards the             base, nearest to RHS 143A. Mature foliage, abaxial surface —             Green to yellow-green, nearest to in between RHS NN137A and             147A; fading to a lighter shade of green towards the base,             nearest to RHS 143A.         -   Venation.—Pattern — Parallel; only the midrib is visible.             Color, adaxial surface — Midrib is green, nearest to in             between RHS NN137A and 139A. All other veins are not             visible. Color, abaxial surface — Midrib is green to             yellow-green, nearest to in between RHS NN137A and 147A. All             other veins are not visible.         -   Petiole.—No petiole; leaves are sessile. -   Inflorescence: No flowering has been observed to date.

COMPARISONS WITH THE PARENT PLANT AND CLOSEST KNOWN COMPARATOR

Plants of the new cultivar ‘AMIHAW1801’ differ from the parent, an unnamed Haworthia pentagona plant (not patented), in the following characteristics described in Table 1 below.

TABLE 1 Haworthia Characteristic ‘AMIHAW1801’ pentagona parent Rate of growth. Faster than the parent. Slower than ‘AMIHAW1801’. Foliage size. Longer and broader Shorter and narrower than the parent. than ‘AMIHAW1801’. General coloration Darker green; remaining Lighter green; becoming of the foliage. dark green under suffused with greyed- high light levels. purple to brown under high light levels. Foliage margins. Coarsely dentate with a Entire to very lightly greater abundance of dentate with a fewer larger, prominent teeth. number of small, inconspicuous teeth.

COMPARISONS WITH THE CLOSEST KNOWN COMPARATOR

Plants of the new cultivar ‘AMIHAW1801’ differ from the closest known commercial comparator, the common form of the species Aloe mitiformis (not patented), in the following characteristics described in Table 2 below.

TABLE 2 Characteristic ‘AMIHAW1801’ Aloe mitiformis Rate of growth. Faster than Slower than Aloe mitiformis. ‘AMIHAW1801’. General coloration Darker green. Lighter green. of the foliage. Foliage margins. Coarsely dentate; Coarsely dentate; teeth along the teeth along the margins are smaller margins are larger and less abundant. and more abundant. 

That which is claimed is:
 1. A new and distinct variety of Haworthia plant named ‘AMIHAW1801’, substantially as described and illustrated herein. 